Biradical Formation by Deprotonation in Thiazole-Derivatives: The Hidden Nature of Dasatinib

06 November 2019, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


The formation of stable organic biradicals by a deprotonation process is reported for a series of conjugated heterocycles that share a Ph-N(H)-2-thiazole structural motif. We characterise the paramagnetic electronic ground state by means of continuous-wave and pulse EPR. We propose a simple valence bond mechanism for a deprotonation-induced formation of paramagnetic organic molecules, based on the interplay between the electronegativity of heteroatomic groups and the recovery of aromaticity to stabilise the biradical species. The Ph-N(H)-2-thiazole motif is found in a variety of biologically active molecules, exemplified here with the anticancer drug Dasatinib, and our results suggest a radical-based mechanism for the protein kinase inhibition activity of the drug. The existence of this structure-property relationship for an elementary chemical motif suggests that biradical species may be more prevalent than previously thought and have an important role in bioorganic chemistry.


organic magnetism
anti-cancer drug

Supplementary materials

Biradicals v8 ESI


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.